Efate, Republic of Vanuatu
Project Summary
KUTh is developing a geothermal power plant on the island of Efate, Vanuatu. Electricity generated by this plant will be used to displace a component of the island’s current diesel based electricity generation. The potential geothermal resources are located on the north side of the island, and a transmission line is proposed to be constructed under Government direction from the site to the existing reticulation grid serving the capital of Port Vila.
KUTh proposes to undertake the development in two phases, each phase comprising a net 4 MW power generation block. This unit size has been selected to match the existing technical specifications of the grid and the anticipated level of demand. The first phase, to be completed in mid-2015, will meet the current overnight base load demand, permitting a 100% plant load factor. The second phase, due for completion in 2017, will be load following.
KUTh geothermal tenements in Efate, Vanuatu.
The Market
The existing power supply on the island of Efate is limited to the area around Port Vila, where electricity is supplied under a concession held by Union Electrique du Vanuatu Ltd (UNELCO), a subsidiary of GDF Suez. There is currently no power supply on the rest of the island.
In 2011 the Government of Vanuatu commissioned a report that recommended the integration of geothermal power into the Efate grid including a new transmission line that will follow the route of the coastal ring road and link the proposed geothermal power plant to Port Vila. This will open up the supply of electricity to communities outside the current concession and facilitate economic development on Efate. As a result, the growth in the market is expected to exceed the long term trend of 4% per annum.
Current electricity sales on Efate exceed 55,000 MWh per annum with a peak demand of 12MW, well in excess of the 30,000 MWh that will be produced by the 4MW geothermal plant planned for Stage 1.
Due to the heavy reliance on diesel generation, the price of electricity is high and fairly volatile; electricity tariffs are reset monthly.
By producing electricity from an indigenous renewable resource, KUTh’s geothermal plant will offer Efate the potential for increased energy security, lower prices and a less volatile tariff setting environment.
The Resource
KUTh has been granted three geothermal prospecting licences by the Government of Vanuatu. The main Takara licence includes a 2 km2 area of 70 °C saline springs close to the northeast coast of the island. The Teouma licence includes a series of warm springs along the north-south Teouma Graben, a significant geological feature which cuts across the whole island. The Epule licence covers an extension of the sub-surface geothermal features from Takara that have been identified from KUTh's exploration.
Each of the licences provides KUTh with exclusive rights to explore for and develop any geothermal resources within the licence areas.
Fieldwork for magnetotelluric survey, December 2009.
After an extensive review of existing geological information and close consultation with local communities KUTh conducted a magneto-telluric (MT) survey around the Takara hot springs in November-December 2009. The survey covered about 35 km2 and yielded a three-dimensional model of the electrical resistivity distribution below the survey area.
The model shows the presence of a complex, highly conductive zone at shallow levels throughout the survey area and an extensive "clay cap" that is strong evidence for the presence of a high temperature geothermal system. These results allowed estimation of an Inferred Geothermal Resource and highlighted strong targets for drilling. This information was released to the market in October 2010 (Vanuatu Inferred Geothermal Resource).
The Takara resource has an estimated P90 inferred resource equivalent to 9.6 MWe over 30 years, which is more than sufficient for the proposed total development.
The Ministry of Lands, Geology, Mining and Energy has extended KUTh’s key Takara prospecting licence for a further 17 months to 1 October 2013. This licence area includes KUTh’s potential drill sites. The Teouma licence, which expires on 1 April 2012 and the Epule licence, which expires 1 April 2013, will be reviewed closer to their scheduled expiry dates.
Development
The next stage of development will be to undertake exploration drilling which will involve drilling 3 slim-hole wells to a depth of approximately 1,500 metres. Prior to committing significant resources to the drilling program, KUTh intends to finalise the agreement of a power purchase agreement with UNELCO, the local utility, and a tariff setting mechanism with Vanuatu’s energy regulator.
The aim of the slim hole drilling program is to confirm and delineate the resource, enabling the design and construction of the steamfield and power plant to commence.
Stage 1, with a generation capacity of 4MW, is planned for completion in mid-2015.